Source and Destination IP of TCP connection
If you consider the format of the TCP-IP datagram.

Source Address: The 32-bit IP address of the originator of the datagram. Note that even though intermediate devices such as routers may handle the datagram, they do not normally put their address into this field—it is always the device that originally sent the datagram.

Destination Address: The 32-bit IP address of the intended recipient of the datagram. Again, even though devices such as routers may be the intermediate targets of the datagram, this field is always for the ultimate destination.

You can get more understanding here.