As for praying in the bathroom, that is not allowed, whether it is a place that is only for bathing or it is a place for relieving oneself, because it is the abode of the devils and the place where a'wrahs are uncovered.
Al-Tirmidhi (317), Abu Dawood (492) and Ibn Maajah narrated from Abu Saâ'eed al-Khudri (may Allah be pleased with him) that he said: The Messenger of Allah (blessings and peace of Allah be upon him) said: "All the earth is a place of prayer except graveyards and bathrooms". The hadeeth was classed as saheeh by Ibn Hibbaan and al-Albaani in Saheeh Sunan al-Tirmidhi.
This hadeeth indicates that prayers offered in the bathroom are not valid, hence it is not permissible to do that except in the case of necessity, such as if the harm that will befall you from your parents is extreme and you cannot pray anywhere else, even by putting prayers together as mentioned above. In that case it is permitted for you to pray in the bathroom.
Shaykh Ibn Baaz (may Allah have mercy on him) was asked about a Christian boy who became Muslim secretly and feared trouble for the sake of his religion if his family found out that he had become Muslim, and he is a young student in school. He does not have a place to pray and he is afraid that if they find out about him, they may send him to a kaafir country or try to make him give up his religion, and he is a person who cannot be steadfast because he is still young. Is it permissible for him to pray in the bathroom?
He replied: It seems that there is nothing wrong with it if he cannot find any other place. If he prays in front of them they may find out about him and try to make him give up his religion. If he cannot find any other place then there is nothing wrong with it, but he may find another place, or he may find a place for some of the prayers and not for others. Hence if he can find another place then he has to pray there, because praying in the bathroom is not allowed, as it is forbidden to pray in graveyards and bathrooms. But if he cannot find any other place, he should not omit (leave out/exclude) the prayer.
Source: http://www.islamonline.com/news/articles/123/A-new-Muslim-girl-fears-that-her-family-will-see-h.html