My daughter is 12, 5ft 4 and weigjhd 90pds is this healthy?

Yes: At 12 years: your child is 90 pounds, and that is at the 45th percentile for weight. Your child is 64 inches, and that is at the 93rd percentile for height. Her weight is perfect and her height is above average.

Probably: That weight for height puts a 12 year old girl at the 10th percentile for body mass index. (bmi). Bmis between 5th and 85th percentile are considered "normal", but within that range, we would still worry over big changes. If a child is losing, or failing to gain weight, it can still be unhealthy. If she has always been thin but well, probably it's ok. If you have concerns, ask your pediatrician.

It depends: Given her weight, height, and body mass index it seems she is tall and thin compared to others her age. If she has always been tall and thin compared to peers and if she seems to take after someone in the family, i would not worry about her weight. Just encourage her to eat healthy. If she has had a recent drop in her weight, i would be concerned and take her in for further evaluation.

Depends: While her height to weight ration (body mass index of bmi) is within the normal range what is really important is if she is still on her normal growth curve. Ask your pediatrician because they should have this information for you. If your daughter is falling off her curve there is reason for concern. If she is still on her curve then it is just the way she is and she is ok if otherwise healthy.

Depends: She's taller than 75-90 % 12yo girls, and heavier than 25-50% of them. Whether that is "healthy" depends on how she takes care of herself, and how she was growing up until now. If she is built like other members of your family she's most likely fine. But if her weight was on the 75% and now is on the 25th, there's an issue. Ease your mind: discuss her "growth chart" with her pediatrician.