How is Pip's family presented? What are the differences in Pip's experience of "family" from children raised in a traditional nuclear family?

When we first meet Pip, we come to understand he is an orphan living with his sister. Pip's sister isn't the friendliest woman in the world and lacks motherly understanding. None-the-less, Pip's brother-in-law (and stand in father) Joe is a wonderful man, who loves the boys and hopes to pass down his trade to him..... just like a son.