I'll be staying here next weekend so I'll report back but having stayed here for at least one night every single year since 1999 I will say it's my favourite spg location in Boston.

Love the views at the Westin Copley (stayed at the Sheraton 3 times and but never had a room with a view there).

As you will be traveling with 4 yr olds do check out the Boston library across the street. It's a good place for some downtime. Quiet comfy reading areas and there are often storytimes or events for children. Apart from that it's a magnificent building so do look inside!