This study is being done to examine the feasibility and impact of the Infant Achievements caregiver coaching treatment on caregiver child-engagement strategies used during play with their infant. The investigators will examine effects on infants' social and communication behavior. This randomized controlled trial will compare caregivers and infants in the Infant Achievements (IA) coaching group to caregivers and infants in the Caregiver Education (CE) no-coaching group. A total of 64 eligible participants (16 children plus their caregiver per group) will participate in the study.

This study is being done to examine the feasibility and impact of the Infant Achievements caregiver coaching treatment on caregiver child-engagement strategies used during play with their infant. The investigators will examine effects on infants' social and communication behavior. This randomized controlled trial will compare caregivers and infants in the Infant Achievements (IA) coaching group to caregivers and infants in the Caregiver Education (CE) no-coaching group. A total of 64 eligible participants (16 children plus their caregiver per group) will participate in the study. Parents in the IA group will be coached, at home twice a week, to implement the intervention by trained research staff. Parents in the CE group will be taught about child development and well-being in their home, weekly, with a weekly follow-up phone call by trained research staff. In both groups: Videotaped caregiver-child interaction data will be gathered in the home. Baseline, post-treatment and follow-up measures will also be collected at the investigators' child development research center.

Families with children between the ages of 8 and 12 months with developmental concerns may be eligible to participate. Developmental concerns are defined as infrequent production of specific communication or social behaviors, or in immature or qualitatively atypical forms. These concerns will be documented via the Autism Observation Scale for Infants, Communication and Symbolic Behavior Scale (CSBS) Infant-Toddler Checklist, and/or Mullen Scales of Early Learning. Recruitment will occur from the Kennedy Krieger Institute (KKI), community agencies, and community events. Recruitment flyers will be distributed within those programs. In addition, a social media blurb will be placed on the KKI and other relevant groups' Facebook pages, KKI Center for Autism and Related Disorders newsletter, KKI websites, and may be sent to relevant local newsletters/magazines for families of young children.

Inclusion Criteria:

• Child participants must be between the ages of 8 months and 12 months at the beginning of the study.
• Family must speak English at least 75% in the home.
• Children must receive an AOSI concern score ≥7 OR
• a T-score of ≤39 on either the Mullen Receptive Language or Expressive Language subscale. OR
• Score in the Concern range on either the Composite or Total Score of the parent-completed Communication and Symbolic Behavior Scales Developmental Profile (CSBS DP) Infant-Toddler Checklist.

Exclusion Criteria:

• History of head injury, seizure disorder, severe aggression or self-injurious behavior, prenatal illicit drug or excessive alcohol exposure.
• Any hearing or visual impairment
• Any severe birth trauma
• Any birth defects or genetic disorders
• Gestational age < 35 weeks and/or Birth weight less than 1,500g
• Cannot be living in foster care.
• Location of in-home visits >35 miles of the Center for Autism and Related Disorders