If you had it done and regret it, then tell them so. I think everyone is entitled to make mistakes (just as long as they don't make the same one several times).
If you had it done because you wanted it and it is part of who you are then tell them so. If they can't accept you for what you are because of a bit of ink then you'll have to work around that.
Don't hide it and have to work your way out of a situation later.
Good luck.
A couple of other thoughts ...
I encourage you to avoid saying "I'm having it removed" because you never know that the future holds. At the point you think you'd have it removed your priorities may have changed and it becomes a postponed project. But if in-laws have expectations you are going to do it there may be some angst that you are not a "man of your word." I would be more inclined to say something less definitive, such as "I intend to have it removed" or "I'm thinking of ..."
The other thing is that, whether you regret the tat or not, it is a part of you and is a part of your character. The experience of getting it and living with it - that can never be taken away. You may decide that it does have meaning to you, or that a slight modification to it may make it more appropriate. If this has recently become an issue I wouldn't be too hasty to make a decision or take action.
Again, just my thoughts. I think it is very important to accept ourselves foremost, and allow others to have non-binding commentary.