OP, here is another idea:

(1) Use your SPG points only for the flights to Mexico (try Cabo), Hawaii, Caribbean (Grand Cayman, Aruba comes to mind). Probably 35K to 50K miles per ticket.

(2) Search on Redweek.com or craigslist and secure a good timeshare rental from an owner during your dates. These 7 night rentals can be had for around $800 to $1500 for the week depending on the size of the unit and quality of the resort.

You and your family would be much happier with these arrangements due to the space available in a timeshare and the convenience of a kitchen for snacks and drinks. All major brands such as Westin, Sheraton, Marriott, Hilton, Hyatt have timeshare resorts. The money spent on the rental will partially come back in savings on meals, snacks, milk, etc. The warmth of the Mexico or Carribean (over Florida) will last for a long time. Send me a PM if you need more details on how to rent a timeshare.

BTW, it is impossible these days to get a free airline ticket with just 25K airline miles to any destination.