Is the husband entitled to reclaim the dowry and gifts if the wife requests divorce before consummation, but after a seclusion with her that did not involve intercourse, knowing that there was a child present in the place during the seclusion? And is he entitled to the full dowry, half of it, or none of it?

If divorce occurs after a valid khalwa (definition) (private seclusion), the woman is entitled to the full mahr (dowry), except in the case of khulʿ (divorce at the wife's instance with compensation). If divorce occurs before a legally valid khalwa, then the mahr is halved, based on the Almighty's saying: "And if you divorce them before you have touched them and you had already specified for them an obligation, then for them is half of what you specified." She is entitled to half the mahr, whether the husband initiated the divorce himself or divorced her in response to her request.

A valid khalwa is one where there is no impediment to sexual intercourse, neither real, nor legal, nor natural. The existence of a physical impediment prevents the khalwa from being valid, and if the door is open such that anyone can enter, it prevents it from being a valid khalwa. Consequently, the full mahr does not become settled, and the husband has the right to reclaim half of it. As for the gifts the husband gave to his wife due to the marriage, he has the right to reclaim them as long as he divorced her before consummation.