:salam2:
Like the other said ukhti - these types of pictures which depict things which are living or are animated and the like are explicitly not allowed in Islaam, for various reasons.
If you have them on the wall to your house, you should do your best to remove them. Imagine - right now out of love you cannot remove it, but at the same time do you not realize that the Angels of mercy are what you are keeping out? Blocking out blessing... doing something which is discouraged? That by doing something as such... you are doing something Allah subhana wa 'tala dislikes?
How can any type of love override this! It cannot surely, and you know this I'm sure.
Therefore, you take it off - your baby sister cries, but how long can she cry? What is a few days of cries, a period of tears in exchange for such a thing? ... ukhti, trust me InshaAllah if you explain to her why you did so, that by removing this we are allowing in the Angels who will be around us and who will bring us good, then surely she will eventually understand. Even if it takes a while, children bounce back quickly enough and she wont hold a grudge too long if you provide her with other outlets.
Anyways, since you understand now alhamdulillah I removed the pictures attached on your post. This way it will not be under your accounting for those who would have seen it here, and will begin the way to reform affairs
May Allah bless you and increase all of us in knowledge
wasalam