The short answer is yes, his widow would have received the Victory Medal and any other campaign medals to which he was entitled (the British War Medal, and possibly others). The policy for those medals was that they were awarded to the individual if they survived, or to the appropriate next-of-kin if they did not. You can see the criteria for the award of the British War Medal and the Victory Medal on the Veterans Affairs Canada website.

It's worth noting that at that time gallantry awards, with the exception of the Victoria Cross and being Mentioned in Despatches, were not awarded posthumously.

The best way to check to see which medals would have been sent to the widow of your friend's relative is to consult his personnel file, which is digitized and available online through Library and Archives Canada. There is a searchable database for Personnel Records of the First World War and you can look him up here. The entire file should be viewable as a PDF.

There is usually a "medal card" in the file which will indicate the service member's eligibility for various medals, as well as to who they were sent. Sometimes they were returned undelivered, especially if people had moved and had not provided a forwarding address. The medal card, or other records on file, will also indicate whether a Memorial Cross was sent. At that time, only widows and mothers were eligible to receive it.

Edit: the family would also have been sent a memorial plaque and scroll.

To use a random example: one of the members of the 85th Battalion killed on 10 August was Clarence John Archibald. You can view his personnel file here. Near the end of the file are cards indicating who received his medals (his foster mother), and the plaque and scroll (his uncle). No Memorial Cross was issued because Archibald died unmarried, and foster mothers were not eligible for the Memorial Cross at that time.

Hope this helps!