Marrying Father Christmas (2018) on Netflix

Plot summary

Miranda Chester went looking for information about her biological father two Christmases ago, and the search brought her Ian McAndrick, her partner, and the family she had always hoped to find, among them Margaret Whitcomb and her half-brother Peter Whitcomb. The couple became engaged last Christmas, and Miranda is now preparing a Christmas wedding with those relatives around her. While she settles the last details of the day, Margaret takes up a romance with someone she knew years ago. Days before the ceremony, a visitor claiming ties to Miranda's late parents contacts her, and Miranda must decide whether to give this new connection a place at the wedding.