VPC Peering and Communication across PVT Subnets

Question

I have VPC1 in N. Virginia and VPC2 in Ohio.

VPC1 has the following configuration:
VPC1 -> 1Pub Subnet in AZ 1 -> One public instance (VEC1)
VPC1 -> 1Pvt Subnet in AZ 1-> One private instance (VEC2)

VPC2 has following configuration:
VPC2 -> 1Pub Subnet in Az 1 -> One Public Instance (OEC1)
VPC2 -> 1 Pvt Subnet in Az 2 -> One Private instance (OEC2)

Security groups are set up in such a way that a user can ssh into VEC1 and from VEC1 to VEC2. And from VEC2 to OEC2. OEC2 can also talk to VEC2.

(1) I SSH in VEC1 using Putty and use winscp to export .pem file into VEC1 so that I can SSH in VEC2 (Is there any way that I don't copy .pem file in VEC1 and still able to SSH into VEC2?

(2) Now I don't have .pem file in VEC2, how do I SSH into OEC2?

Pls revert.

Sanjeev