She's the country's youngest ever Premier and the second woman to hold the top job.

Her rise follows a tumultuous week marked by the dismissal of her predecessor Seta Thaweesin and her father, Ex-PM Thaksin Sianawat's recent royal pardon.

As she takes office, questions loom over how much influence her father will wield in her administration.

Saksit Sarasawat reports from Bangkok.

Within the span of a year, Thailand has now Prime Minister No. 2 at their helm, and her name is Petongtan Sianawat.

In a ceremony on Sunday morning, Ms. Petongtan was given the royal command, confirming her endorsement as the head of the new Thai government and the order to form a cabinet of ministers.

She is now the country's youngest Prime Minister and the second female after her aunt Yingluck, making her the third Sianawat family member to assume office since her father Thaksin over 20 years ago.

In her short speech after the command, she thanked His Majesty and the MPs that voted for her on Friday.

She said that she will carry out her duty with an open heart to move the country forward.

The presence of her father, the ex-Prime Minister Thaksin Sianawat, drew particularly a lot of interest, given that he was given a royal pardon just a day ago that effectively ended his parole early.

Thaksin returned to Thailand almost a year ago after 15 years of self-exile, and while he was right away sentenced for abuse of power and corruption from his rule back then, he was released on parole just half a year later after spending that time in hospital instead of a prison cell.

And with him now being effectively a free man, the question is not if, but how much Thaksin is going to influence the new government even more.

After all, he is the patriarch of the ruling pro-Thai party, which is led by his daughter Perthongtan.

Speaking to the media after the ceremony, Ms. Perthongtan faced exactly that question multiple times.

I hope I can ask him for advice anytime that I want, but not all the time, 24-7 like that, because it's not possible.

I am my own person, and I have my own things and my own goals that I have to achieve in the future.

But of course, all the comments from him value to me, and yes, I just wish that I could work with everybody, including my dad as well.

This caps off, for now, a turbulent two weeks of Thai politics that began with the dissolution of last year's election winner, the opposition Move Forward party at the hands of the Constitutional Court.

A week later, that same court then dismissed Prime Minister Sertar Thaweesin for ethical misconduct in appointing an ineligible cabinet minister, which sparked off frantic and furious backroom negotiations for his successor that culminated in Perthongtan Shinawatra now becoming Thailand's 31st Prime Minister.

But all this political upheaval is not making the economic challenges that the ruling pro-Thai party is promising to fix any smaller.

And also, there's a growing conflict brewing in the background between all the political factions, mainly Thaksin and his rivals that he made a deal with that allowed him to return to Thailand in the first place.

So all this could not only upend his daughter's new government, not only Thaksin's own legacy, but Thai democracy as a whole.

Saksit Saiyasomat, CNA, Bangkok.