I wouldn't bother. Picture books aren't good and if dc2 is just beginning to read sentences, she needs the pictures to prompt her and I think she needs paper books. My DS is 8 and I think he would either lose or break a kindle within a week.
If you are worried about the space at hone, why not just take them to the library?
Just wondering if I should get my children a kindle? We literally have 100's of books and with dc4 on the way not enough room for an ever expanding library. My eldest (7) is an avid reader and my 4 year old is just beginning to read in sentences.
If we were to buy one is there one which the little one (2) would be able to look at picture books on? Either way what would you recommend for us? We already have an iPad so don't need a tablet.