Should my daughter also convert to a mslim when I get married

How old is your daughter. If there is a choice involved here, why not let her chose whether she wants to convert or not?

I agree with JH76 that age in this case is important.

Is your child old enough that she will know the difference? How important to you is it that she changes her faith with yours?

But I also have to ask you how strongly do you feel about converting to Muslim? Are you head over heels about it or are you doing it because your future spouse is Muslim? This may affect your child's views on the change.

I also have to ask if you practiced anoher religion before this marriage where your child will become confused. If you've drilled one thing for years and now you're on a completely different page, it may cause the child great confusion and possibly distress... so back to the first question- how old is she?