Heat olive oil in a large pan over medium heat. Add diced chicken breast and cook until the chicken is golden brown and fully cooked through, about 5-7 minutes.
Stir in the minced garlic and cook for 1-2 minutes until fragrant. Add the penne pasta and chicken broth directly into the pan with the chicken. Bring it to a simmer and cover. Let the pasta cook for about 10-12 minutes or until tender.
Once the pasta is cooked, reduce the heat to low and stir in the milk, cream cheese, pesto, and parmesan cheese. Stir continuously until everything is well combined and the sauce is creamy.
Garnish with fresh basil if desired. Let the dish cool before serving it to your toddler. You can cut the pasta into smaller bites if needed.