Check to make sure the choke is actually closing completely enough to affect a cold start up.
The little clamp that holds down the choke cable may have let the cable slip a bit out of adjustment, causing the choke not to close all the way.
And lose the ether based starting fluid, that ain't no Cummins diesel engine you're feeding it to.
Spray carburetor cleaner is a much gentler product to use if needed.

Ditto losing that ether starting fluid - else he will soon be in the market for another $$$$$ engine. Rattlecan carb cleaner as Mownie advises much better.
Remove air cleaner from engine carb, have assistant operate choke, watch for for full closure of butterfly plate in carb throat (may need mirror depending on orientation of carb). Adjust as Mownie says.

Beyond that, it would be good to know that the fuel pump has output at that first start of the day. A check valve in the pump or poor fuel lines would then be suspect. The carburetor bowl could be dropped and note whether water or debris is present and then you can physically note if the shut off solenoid on the bottom is sticking and not reacting right away. Model, spec numbers and whether the carb has an accelerator pump on the side could be helpful information. A link to service manuals and parts look up is below.

Here is a link that might be useful: Kohler Plus