Is it normal to kiss family members on the lips?
Depends.It depends
Yes, some families kiss on the lips as a casual sign of affection, while others stick to cheek kisses or hugs. What matters is that everyone involved is comfortable with it and can say no without pressure.
Family habits vary a lot. In some households, a quick kiss on the lips between relatives is an ordinary greeting or goodbye; in others, it would feel unusual. Neither custom automatically means anything romantic or sexual.
The key is comfort and consent, especially as kids get older: anyone can prefer a cheek kiss, hug, or no physical greeting at all. A respectful family makes room for that without teasing or insisting.