Why has it took my mate six years to move his girl into his flat that he's had for almost 4 years?

My mate posted his girlfriend of 6 years is moving in with him soon... Ok but why so long? And why haven't you even had one kid yet you are both 31. I find the whole thing weird? My other mate said it's none of my business. What do you guys think? Should I say something.

Why has it took my mate six years to move his girl into his flat that he's had for almost 4 years?
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