Spring and Fall and great seasons for children's portraits, especially in a field or meadow where I have some back light to use from the setting sun in the afternoon. Part of my 'where to take family portraits outside' would involve the Evergreen Brickworks in Toronto's Don Valley.
It is a wonderful place to take your professional family photographs. Head out to the back behind the brick buildings to take advantage of the nature trails in what used to be a quarry. Strictly speaking, the Brickworks require a permit for photography so it's best to check with me regarding the details of that. It is something that the subjects need to organize (they won't let photographers book it on behalf of a client).1/400; f/4.0; ISO 250; 190.0 mm.