Thank you Maureen,
Now I share your concern with the length of Benjy's constipation. Though with the improving weather, it may be that he is going outside (so keep an eye on that). But in any case, if we are worried about constipation and if he is comfortable in his belly, not being sick, and isn't straining to go; then we can try a few home treatments to see if we can get things moving for him properly.
Now to start, you can offer some cow milk. Kitties are like little lactose intolerant people, and while the love milk it can move things down the gut a bit quicker (ie. Cause mild diarrhea in an unconstipated cat). If he is mildly constipated, this might just get things moving in the right direction. Another option that can help here would be cat
hairball medication (ie. Catalax). This is available from the vet or the pet shop. It works to lubricate the gut and can facilitate the movement of hard feces out of the rectum. And this would be much better then olive oil, since that would absorb in the gut too quickly to help move feces down the lower GI.
Alternatively, you can administer a small volume of Miralax (1 tsp per 24 hours), lactulose (LINK) or food grade liquid paraffin or mineral oil orally. All should be available OTC at the chemist or from your vets. Ideally, instead of offering it direct, do consider adding it to a food he likes (ie tuna). This is much safer, since giving directly could lead to aspiration if he struggled when it was given.
Finally, if he is a cat that struggles to pass feces most of the time, you can consider increasing his dietary fiber to help push the feces through his GI. To do so, you can consider mixing some canned pumpkin or a 1/4 teaspoon of unflavored Metamucil/Benefiber into his food daily. Just like people, these can restore fecal output regularity. I would offer these with wet food to ease him eating of it, while making sure we are getting water into him (as canned food is 35% water). And alongside this, promoting him to drink well is also advisable (since constipation can be due to dehydration).
Overall, if he isn't straining or in discomfort (and we are sure he's not eaten something that could block the gut), we can use the above steps to get things moving for him. While doing so, we do want to keep a close eye on his fecal and urinary output. If you try the above but don't see feces within the next 12-24 hours, then we'd want to consider getting your vet involved. Severe impactions of feces are usually secondary to more serious diseases, so if he doesn't respond to our gentle colon cleaning treatments, then he may require more aggressive treatment (ie enemas under sedation).
All the best,