Actor Ryan Kwanten, from the hit TV series True Blood, has reached out to families of sick children by giving them a chance to watch his show.

After five years as Vinnie Patterson on Home and Away, he transferred to the US and is now a rising star on one of the country's well-known TV shows.

Kwanten's role on the US vampire drama True Blood is a charming but promiscuous ladies man.

On Monday, he returned to Sydney, courtesy of Telstra, for the release of the new T-Box home entertainment system.

He went to the Ronald McDonald House in Randwick and donated a set-top box for the families of children with acute conditions living at the centre.

Telstra will give one T-Box to each Ronald McDonald House in the country in the coming months.

T-box allows viewers to watch BigPond TV, HD free-to-air TV, and YouTube videos from the one set-top box, and it can also be used as a personal video recorder.