Breast augmentation and lifting my baby

It’s generally recommended to avoid lifting anything over 10–15 pounds for at least 4–6 weeks after breast augmentation and/or lift to allow proper healing and avoid complications. This includes lifting young children. That said, many mothers manage by planning for extra help during recovery.
You don’t need to wait years—timing the procedure when you have adequate support at home can make recovery smoother and safer.
Erman AK, Dr. MD, Plastic Reconstructive & Aesthetic Surgeon

Typically you will have lifting restrictions in place for anything over approximately 10 pounds for four to six weeks after surgery. This does not mean you cannot care for your children at all, but rather you'll need some help for direct lifting. Speak with your surgeon about your concerns.

It depends on the post-op instructions that are given to you by your surgeon. Each surgeon has their own instructions so one could advise 4 weeks while another may advise longer. However, either way, you should expect to have some restrictions on lifting and physical activity for a certain length of time, and it could negatively impact your recovery and your safety if you don’t follow them. It would be a good idea to speak with your surgeon to find out what they advise, and then decide what to do from there.