The Latino Emerging Adult (LEA) Parent Support scale was designed by the research team. Participating parents self-administered this online computer-based survey twice during the study--at baseline and approximately 3-4 months later, after the completion of the intervention program. The scale includes 8 items (e.g., Even if [child's name] doesn't listen to me one time, I still know that I can get through to him/her the next time; [child's name] comes to me and talks to me about important issues in his/her life; I generally know how to connect with or reach out to [child's name] when they need my support). Answer choices include: 1-Strongly disagree; 2-Disagree; 3-Agree; 4-Strongly Agree. Higher scores indicate higher parent support. The Cronbach's alpha was .82. (Citation: Center for Equity Promotion. [2019]. Latino Emerging Adult (LEA) Parent Support scale. University of Oregon.)

Three items from the University of Michigan's Monitoring the Future survey were used to appraise alcohol use (Johnston, L. D., O'Malley, P. M., Bachman, J. G., Schulenberg, J. E., & Miech, R. A. (2015). Monitoring the Future national survey results on drug use, 1975-2014: Volume II, college students and adults ages 19-55.). Items include:

1. Have ever tried even a few sips of alcohol? Yes No (if no, skip to #3)
2. If YES: How old were you when you first tried at least a few sips of alcohol? _____ years old
3. During the last 3 months, what was the HIGHEST number of drinks that you drank in a single day?

Twelve items from the Monitoring the Future survey were used (Johnston, L. D., O'Malley, P. M., Bachman, J. G., Schulenberg, J. E., & Miech, R. A. (2015). Monitoring the Future national survey results on drug use, 1975-2014: Volume II, college students and adults ages 19-55). Exemplar items include: During the last 3 months, about how many days did you drink until it affected your ability to make decisions?; How many times in the last 3 months did you use other drugs after you had been drinking?; and, In the past 3 months, how many times did you ride in a car when you knew the driver was drunk or high?

The Latino Emerging Adult (LEA) Drinking-related Harm Reduction Behaviors scale was designed by the research team. Participating emerging adults self-administered this online survey twice during the study--at baseline and approximately 3-4 months later, after the completion of the intervention program. The scale includes 13 items (e.g., If one of my friends is really drunk, I make sure that person is safe; If I have been drinking too much I feel comfortable finding a ride home with a sober driver or finding a place to sleep; In my group of friends, if someone has been drinking too much we make sure that he/she doesn't drive). Answer choices include: 1-Strongly disagree; 2-Disagree; 3-Agree; 4-Strongly Agree. Higher scores indicate EAs practice more alcohol-related harm-reducing behaviors. The Cronbach's alpha was .93. (Citation: Center for Equity Promotion. [2019]. Latino Emerging Adult (LEA) Drinking-related Harm Reduction Behaviors scale. University of Oregon.)

Emerging adult participants respond in an online survey to the 10-item Perceived Stress Scale (PSS-10; Cohen, S. and Williamson, G. [1988]. Perceived stress in a probability sample of the United States. In S. Spacapan & S. Oskamp [Eds.] The social psychology of health [pp. 31-67]. Sage Publications, Inc.). Answer choices range from Never = 0 to Very often = 4. Responses are summed with higher sum scores reflecting higher perceived stress. The Cronbach's alpha for emerging adults in this study was .82.

Parent participants respond in an online survey to the 10-item Perceived Stress Scale (PSS-10; Cohen, S. and Williamson, G. [1988]. Perceived stress in a probability sample of the United States. In S. Spacapan & S. Oskamp [Eds.] The social psychology of health [pp. 31-67]. Sage Publications, Inc.). Answer choices range from Never = 0 to Very often = 4. Responses are summed with higher sum scores reflecting higher perceived stress.

Sixteen items from the Bicultural Identity Integration Scale (BIIS-2) were used to capture variation in emerging adults' experiences of acculturation. (Huynh, Q. L., Benet-Martínez, V., & Nguyen, A. M. D. [2018]. Measuring variations in bicultural identity across US ethnic and generational groups: Development and validation of the Bicultural Identity Integration Scale-Version 2 [BIIS-2]. Psychological Assessment, 30[12], 1581.). Exemplar items include: I feel part of a combined culture that is a mixture of Hispanic/Latino and American; I find it difficult to combine Hispanic/Latino and American cultures; I do not blend my Hispanic/Latino and American cultures. Answer choices range from 1 (strongly disagree) to 5 (Strongly agree). The scale taps cultural blendedness versus compartmentalization and cultural harmony versus conflict, and final scores are averages.

Ten items from the Steinberg et al. Future Orientation Scale were used (Steinberg L, Graham S, O'Brien L, Woolard J, Cauffman E, Banich M. [2009]. Age differences in future orientation and delay discounting. Child Development. Jan-Feb;80[1]:28-44.) The 10 items include question numbers 2, 3, 4, 5, 7, 9, 10, 12, 13, 15 across 4 sub-scales including Planning Ahead, Time Perspective, Anticipation of Future Consequences, and Anticipation of Future Consequences. All items are scored left to right on a scale of 1-4. Reverse score items 1, 3, 4, 6, 8, 11, and 14, so that higher scores indicate a stronger future orientation.

This 12 item scale appraises parents' hopes for their emerging adult children's future. Answer options range from 0-Not at all true to 3-Very true. Exemplar items include: It's important to me that (my child) continues her/his education after high school; It's important to me that (my child) graduates from college; I know what (my child's) goals are for her/his future; and I help (my child) make plans and take steps towards her/his goals for the future. Citation: Center for Equity Promotion. [2019]. Latino Emerging Adult (LEA) Parent Hope for Emerging Adult Future scale. University of Oregon.)

Seven items were used from the American Identity Measure (Schwartz et al [2012]. The American Identity Measure: Development and validation across ethnic subgroup and immigrant generation. Identity: An International Journal of Theory and Research, 12[2], 93-128.). Exemplar items include: I am happy that I am an American; I have a strong sense of belonging to the United States. Answer choices range from 1 (strongly disagree) to 5 (Strongly agree). Higher scores indicate higher American identity affirmation.

Items from the Multidimensional Acculturative Stress Inventory for Adults of Mexican Origin (MASI) were used (Rodriguez et al. [2002]. Development of the Multidimensional Acculturative Stress Inventory for Adults of Mexican Origin. Psychological Assessment, 14[4], 451-461.) The MASI is a 36-item stress measure that assesses acculturative stress among persons of Mexican origin living in the United States;10 items were selected that are part of factor 3: pressure to acculturate, and factor 4: pressure against acculturation. Response options begin with a stem: Has this occurred in the last 3 months? Yes or no. If yes, how worrying/stressful has this been? Follow-up response options range from 1-Not at all worrying/stressful to 5-Extremely worrying/stressful. Final scores reflect incidence of stress exposure (sum of "yes" stem responses) and stress responsiveness (average of follow-up stressfulness scores).