His father took pictures of him when he was small relieving himself and taking a bath, and his siblings can see them now!

Firstly: 

Contemporary scholars differed concerning the ruling on making photographic and video images. In the answers to questions no 10326 and 12786 we stated that the correct view is that both are haraam, if the images are of animate beings. 

In the answer to question no. 10668 we stated that it is haraam to take pictures even if it is for the sake of memories. 

If this is the view of scholars concerning pictures even if they are of children who are praying, then it is more likely to be haraam if they are pictures of children relieving themselves or taking a bath naked! 

Many people are heedless about this issue, and they take pictures of their daughters when they are small, then when they grow up and get married, those pictures are passed around, and people look at them. Would that this was limited only to mahrams, but they are even passed to non-mahrams! And it becomes difficult to collect these pictures and video tapes to destroy them. The same may be said with regard to taking pictures of boys when they are naked and taking a bath. As for taking pictures of them when they are relieving themselves, then this combines the prohibition on taking pictures and uncovering the ‘awrah at one time, and no one should look at them. This is an action which is contrary to modesty and chastity, and sound fitrah (human nature). 

What parents must do is immediately hasten to destroy the pictures that they are keeping of their children – male and female – and especially those in which they are in a state in which it is not appropriate for anyone to see them. This is what we advise your father to do. He has to respect the prohibition on seeing ‘awrahs and pay attention to your feelings about showing these pictures and films to your brothers and other people. 

Even if we assume that making pictures is permissible in principle, and that making images of such scenes is halal, the parents have no right to keep such pictures and show them to others now that you have reached this age and are upset by that, or it causes others to make fun of you. 

If he does not respond, then ask your brothers not to look at these pictures and films; may Allaah rid you of this problem and relieve you of this worry and distress. 

And Allaah knows best.