Announcing to someone who has suffered loss...

Sammy
We were planning to announce to my husband's family on Christmas in a fun way, but I'm not sure that's a good idea because one of my SILs suffered a second trimester miscarriage this year and I don't want to ruin Christmas for her. 
My husband has a huge family with 13 siblings and all the spouses and kids to go along with it. On Thanksgiving another of my SIL's who lives out of town announced on FB that she is expecting (within a week of me I might add) and I saw the look on my other SIL's face when she saw people announcing pregnancies.
My husband wants to go through with announcing, but I want to make sure we're sensitive to her. Would it be sufficient to give her a heads up the day before via text so she and her husband can take it in on their own without being in front of everyone and still do it in a fun way or should we just not make a big thing of it?
If you've been through a loss or in a similar situation I would love some input on this.