Above, we have a late 1960 aerial view of the mall site. The original shopping centre is seen in the upper left corner. A newly-built South Wing extends toward the spaceship-shaped Curling Rink at the bottom of the image.
Photo from https://images.thestar.com / The Toronto Star

In 1961, the T. Eaton Company added a bona fide anchor store to the retail hub, which was now officially known as DON MILLS CENTRE. The 26th unit in the Toronto-based chain, the store was the first suburban branch built by "Eaton's of Canada".
Drawing from http://www.thedepartmentstoremuseum.org 

Grand opening day at the shiny new Eaton's Don Mills. The store, officially dedicated in July 1961, encompassed over 100,000 square feet.
Photo from https://www.blogto.com

By the early '60s, the centre has been expanded exponentially. Its vast, 2-level parking area can accommodate 4,000 autos. On this plan, the original mall is shown in black. A Dominion supermarket, Civitan Arena, Curling Rink and single-sided South Wing were completed in 1959 and 1960. These are shown in dark gray. Eaton's, a South Wing addition and freestanding cinema were finished between 1961 and 1963 and appear in light gray.