next to him/her
Miren al hombre que tienen a su lado.
Look at the man next to you.
De repente, el príncipe notó que su guardaespaldas no seguía a su lado.
Suddenly, the prince noticed that his bodyguard was no longer by his side.
Alguien estaba sentado a su lado.
Someone was sitting next to him.
Cuando estás a su lado, te olvidas de todo.
When you're by her side, you forget everything.
Quince años, ocho meses y nueve días, estuve a su lado.
For fifteen years, eight months, and nine days, I was by her side.
— American Gangster (2007)
El tiempo que le quede me gustaría estar a su lado.
I would like to be by your side for the time you have left.
— Zeta (2026)