Infer family type, size from reviews
I can think of two options:


Train a custom supervised tagger for your data, typically with a sequence labeling method such as CRF. This will require a quite large amount of annotated data (and a specific formatting), but if done well it should give you quite accurate results.
Use manually defined patterns based on keywords (such as "My * and I", "family", "friends") directly associated with a predefined category, and match these patterns in the data. You can do several iterations of defining new patterns for cases that are not matched, thus refining progressively. Depending on your data and how far you go with this you should be able to correctly match most cases, possibly reaching as good accuracy as a tagger for much less work.


Btw be careful how you represent your data: the same user id might not always give you the same group of people since they can go to a restaurant one day with their family, the next day with their wife, the day after with their mistress, etc. Also a "family of 2, expecting" usually becomes "a family of 3" after 9 months ;)