my daughter has become really interested in babies and playing mommy and when she gets video time on…

my daughter has become really interested in babies and playing mommy and when she gets video time on my phone she watches mommy videos of dolls having babies. nothing inapropriate. I feel like she's telling me she wants a sibling. she also helps with my niece that's 3 months. my hubby and I are planning to have another baby but she hasn't heard us talking about it. advice?