A foster parent company which looks after children with special needs has been sold by its private equity owners for £36 million.

By the Bridge, based in Borden, near Sittingbourne, has been acquired by behavioural health service firm Cambian Group in a sale which gives owners Apposite a return three and a half times their original investment when they took over the business in 2006.

The fostering organisation, which has another office in Sittingbourne, has grown the number of children it looks after by five times under its private equity owners.

Founded in 2002, it has also increased revenues by four and a half times to about £25 million under Apposite, a fund which invests in healthcare companies.

It has opened five new offices across the country and today cares for 516 children with high severity needs in 346 families.

The firm’s local management team will remain unchanged and Nicola Tunbridge, an original founder of the company, will become managing director of the enlarged Cambian Fostering division. She has led By the Bridge over the last seven years.

She said: “I look forward to integrating By the Bridge and Cambian Foster Care into one highly capable and united team to continue to make a significant difference to even more children lives.”

Steve Adkin, a partner at Apposite who also served on the board of the Kent company, said: “By the Bridge has built a reputation as the highest quality specialised therapeutic foster care provider, allowing it to capture the growing demand from local authorities for outstanding foster care services in the UK.

“By the Bridge has built a reputation as the highest quality specialised therapeutic foster care provider, allowing it to capture the growing demand from local authorities for outstanding foster care services in the UK..." - Steve Adkin, Apposite

“We worked closely with a dedicated and talented team driving the company’s growth plans while making sure it retained its unique culture of empowering foster parents and delivering the best possible care for the children it looks after.

“Cambian are an ideal partner to build on By the Bridge’s recognised expertise and I am confident they will continue delivering outstanding outcomes for local authorities and fostered children.”

Cambian employs about 6,800 people across 286 purpose-built sites in England and Wales, comprising 26 schools, 38 hospitals, 219 specialist homes and 3 fostering offices.

Its services focus on children and adults with high-severity needs.

Cambian Children Services chief executive Anne Marie Carrie said: “I am delighted with this acquisition which is in line with our strategy to increase our scale and expand the range of services that we offer to local authorities.”

An earlier version of this article said By the Bridge had been sold for £44 million. This is the total value of the deal, while £36 million is the enterprise value, cash free and debt free.