Final answer:
Researchers would advise Cruz and Eva to support their son's involvement in team sports and mixed-gender friendships for his social development, while also ensuring he balances time between sports, academics, and family activities.
Step-by-step explanation:
Cruz and Eva's seven-year-old son is in a crucial phase of his development where peer relationships and participation in group activities such as a baseball team are greatly shaping his social skills and self-concept. Researchers focused on child development might advise Cruz and Eva to continue encouraging their son's involvement in team sports, as it can bolster cooperation, sharing, teamwork, and physical health. Additionally, researchers might suggest that they foster his mixed-gender friendships, as these are becoming increasingly significant at his age and aid in the development of social competence.
To ensure a well-rounded development, they might also be advised to make sure their son balances his time between organized sports, school responsibilities, and family activities. This balance would help him develop a range of skills and prevent any single aspect, such as sports, from overshadowing important areas like academic performance. With their son exhibiting obedience and the ability to make friends, these suggestions should supplement what appears to be a healthy developmental trajectory.