Two siblings from the Prissanananthakul family on Monday joined the Bhumjaithai Party after their father last week severed ties with the Chartthaipattana Party.
Paradorn and his brother, Koravee, received a warm welcome from Bhumjaithai key figures including party leader Anutin Charnvirakul who said the pair would be an asset.
It was reported that during the live stream of the application process, Chartthaipattana Party leader Kanchana Silpa-archa posted a message in the comments saying "Congratulations!".
Mr Koravee yesterday gave the reasons he picked the Bhumjaithai Party.
"The party's goal is to push ahead with policies to address people's problems. I think it's time to stop asking if the party is 'pro-military' or 'anti-military'. The focus should be people's well being," he said.
He said that he and his brother hope to make the Bhumjaithai Party one of the country's political fixtures.
Mr Somsak, the right-hand man of the late former prime minister Banharn Silpa-archa, who was also the Chartthaipattana's patriarch, announced his decision to end his role in the party last week to preempt any move that might lead to the party being dissolved.
He expressed concern that his engagement with the party may prompt an investigation -- something the Pheu Thai Party is facing over its alleged connection with fugitive prime minister Thaksin Shinawatra.
The Prissanananthakul siblings were the latest batch of Chartthaipattana members to defect to the Bhumjaithai Party after former MP for Chaiyaphum Chawengsak Rengpaiboonwong, former Uthai Thani MP Chada Thaiseth and former Si Sa Ket MP Siripong Angkhasakulkiat.
Mr Anutin said several politicians have joined the Bhumjaithai thanks to its position, noting the party has high-calibre people who could form a strong government or an efficient opposition.
He insisted that the party has no particular target as to how many House seats it should win, but it would do its best.
He also added that Mr Paradorn is likely to run for a constituency seat while Mr Koravee is likely to be named on the party list.