The daughter from that family knows about it and has no problem with it.
Although from a shar'i perspective this might not be obligatory, but one is asked it would be haram to lie and not tell the truth.
Also, ethically it is important for both sides to be transparent and clear about everything. Present everything to each other, and it is up to both sides to decide and agree, or disagree.
The problem with concealing such information is should it surface later on, it will become very difficult to contain and could lead to deep issues.