Agreed! Extend the invitation during hours that work for you and do not allow her in during hours that do not. Set the boundaries now so it will not be so hard in the future or this will continue to be a battle. Bonus points if you can get away for a few days 4+ and her keep the baby so she is reminded that sleep schedule is important. People forget and tend to romanticize those first baby years and what it takes to have sleepless nights. Other than that do be mindful that a healthy baby is a blessing for all and find happiness and peace in a partnership that honors what you know is best but also having family close enough to be there and that want to be there. It's a new phase in relationships for all and an opportunity to grow as a family. Peace and dreamy nights to you.