meaning difference

[Allifathima]

1. He took her hand.
1a. He took her by the hand.
2. Both boys were taken prisoner.
2a. Both boys were taken as prisoner.
What is the meaning difference between #1 & #1a and also between #2 & #2a?
Can I say as below:
"Both boys were taken prisoners."

[Dozy]

Typically, 1a has more of a sense of leading someone, whereas 1 is often just affectionate or comforting. However, this distinction is not completely clear-cut.

The usual expression is "taken prisoner", regardless of how many people are involved.