Complex sentence: Before she began forming two-word sentences she could both ask for something and associate an object with someone, which was normal, but unlike young children she could also ask about memories or future events which had previously been mentioned.
Split into simpler sentences: Before she began forming two-word sentences she could both ask for something and associate an object with someone, which was normal. Unlike most young children, though, she could also ask about memories or future events which had previously been mentioned.