In Feb I went through this when my border collie had to be put down in our home.
Tia was six months old then and even a couple of days before Jessie was put to sleep she wouldn't leave her side. (Jessie had her second stroke) I put a thread on 'Do dogs have a sixth sense.?
The following days were painful for everyone in our house including Tia.
At lunchtimes is usually our play and training times , but she didn't want to know.
It just broke my heart over again thinking that she too is suffering.
Even our walks wern't the same without Jessie.
But there is hope and a know its an old cliche but time is a great healer and your baby will get over it. Show her extra love if thats possible.Sending hugs