What about getting a buggy board for your toddler?
I had the Cosatto Duet Lite but I hated it. Was too heavy and hard to get up kerbs with Nathan in the front and I didn't like the fact it was so long and infront of me when crossing roads etc. Also, when Kieran got older he wouldn't be able to see much being stuck at the back.
I got a cheap side by side one and much prefered it. The only problem was getting through narrow doors.
Although tbh I have got rid of both of the above now because I wear Kieran and have Nathan in the single pushchair or have Kieran in the single and Nathan on buggy board.