One party that cannot be part of a “gift” for a down payment is the seller. They qualify as a person with a vested interest in selling the house, which excludes them from being able to write you a check. They can, however, make concessions or offer credits (typically limited to a fraction of the sales price) at closing in designated amounts to cover specific items such as repairs on the property.
Lenders can play a role in helping certain borrowers – often those who qualify as low- to moderate-income – get to the finish line via down payment grant programs and lender credits that help offset closing costs. Not every lender offers down payment assistance options, so you’ll want to ask about availability as you compare loan programs.