No Vent on Toilet Drain?

[Esachs4]

I am in the process of remodeling my bathroom and I noticed that this is no vent on the toilet drain.
It is right above the main waste line. Is it being vented through that? Should I add an additional vent?
See pictures below:

 

[Terry]

Sometimes a toilet will be vented by a nearby lav or tub, assuming those are vented properly.

 

[Sponsor]

 

[Esachs4]

Yes, there is a sink nearby with a 2'' vent. See below. Is this sufficient?

 

[Terry]

The lav would be venting the toilet.

 

[Esachs4]

Ok, thank you!