Why?

I have more than 16 years experience of carrying babies of all age and sizes and my brother doubt my ability to handle his 4 months old son. Is this an insult or an act of an overly protective father? I told him, don't let it be a burden to care for your children. Since the birth of my niece, the best and only way of taking of his kid is over-protection. Frankly speaking, it is very tiring to be at his place. We have to be at our 'best' behaviour and restricted movement. At some point, I felt very unwelcome and disappointed.

Why is my brother behaving this way? He can't trust us, who is suppose to be his closest kin other than his wife and kids? I don't have to make the effort to get my mum to visit them, but if I don't do it, who will? Asking my brother to visit my grandma with his family is like the toughest thing and he always have ton of excuses. He is busy, tell me who is not???