confused grandparents

Our daughter and her hubby, have 2 adopted babies, ages 2 1/2 and 10 months, both babies were adopted at birth and both are open, in-state, adoptions. Our daughter feels more obligation to the b-parents than she does to us ... she actually referred to them as 'their parents' in a conversation we had recently about the kids. she stated that she feels more obligated to make 3 hour trips to see 'their parents' at their beck and call, than she does a to make a 20 minute drive to our home or to visit other family members. I need some input here. What can I do to help her realize those are HER BABIES ? She works full time and I honestly don't feel she has had the time to fully bond with either of them. Am I wrong in feeling hurt and confused about this? Thank you for ANY input you can offer! I want to understand.