SINGAPORE - Prime Minister Lee Hsien Loong raised questions about the role of his brother Hsien Yang and sister-in-law, lawyer Lee Suet Fern, in preparing the seventh and final version of the late Mr Lee Kuan Yew's will, in a lengthy statement issued by his lawyers on Thursday (June 15) night.

The document differed markedly from its previous version, in that it gave equal shares of their father's estate to all three of his children.

This was a reversal of a decision that the late Mr Lee had made in his second-last will, in which Dr Lee Wei Ling, his only daughter, was given an extra share of the estate.

The other key difference was the inclusion of a clause stating that the late Mr Lee wanted his house at 38, Oxley Road demolished after his death.

The clause had been in the first, second, third and fourth wills, but was not in the fifth and sixth ones.

In his statement, PM Lee quoted e-mails exchanged by his family members, and recounted the series of events that "led him to be very troubled by the circumstances surrounding the last will".

He also disclosed his sister Wei Ling once held "grave suspicions" that the removal of her extra share of the estate was "instigated" by her brother Hsien Yang and his wife.

PM Lee said his father changed his mind on giving Wei Ling an extra share after discussions with Mr Lee Hsien Yang and his wife.

Unlike all the previous wills, the final one was not prepared by their cousin, Ms Kwa Kim Li, a lawyer at Lee & Lee, the firm co-founded by the late Mr Lee and his wife Kwa Geok Choo.

Instead, it had been prepared by lawyers from Mrs Lee's law firm.

This happened after Ms Kwa was removed from an email list regarding the last will on Dec 16, 2013, by Mr Lee Hsien Yang.

He told his father he could not get in touch with Ms Kwa and believed she was away.

He also said he thought it was not wise to wait for her to return and suggested having lawyers from his wife's law firm, including a partner of the firm, prepare the will and witness the signing.

On Thursday (June 15), PM Lee questioned the decision, saying that it was unclear what efforts his brother had made to get in touch with Ms Kwa.

Ms Kwa had also said to Mrs Lee that she did not receive an email sent by her immediately before being removed by her husband from the email chain.

PM Lee said it was not clear why his brother thought there was an urgency to the signing of the last will.

"It is however interesting that he suggested that his wife, clearly an interested party, and her partners would prepare the new will," he said.

He also cited emails showing that in the space of 41 minutes at night, Mrs Lee had seen to the preparation of the new will and had one of her colleagues to be on standby to get it signed by the late Mr Lee.

The next morning, he signed the final will in the presence of two lawyers from Mrs Lee's law firm, then called Stamford Law Corporation. It is now known as now Morgan Lewis Stamford LLC.

PM Lee noted that the two lawyers, Mr Bernard Lui and Ms Elizabeth Kong, were present at his father's house for "15 minutes only, including the time for logging into and out from the property".

"They plainly came only to witness Mr Lee signing the last will and not to advise him," he said.

Neither he nor his sister were copied in the emails on the last will.

PM Lee also questioned the re-insertion of the demolition clause into the final will, when the change the late Mr Lee had wanted only concerned the share of the house which Dr Lee was to get.

He also recounted how he went to look up old family emails, after he and his brother disagreed over whether the house should be immediately demolished during the reading of the last will.

At PM Lee's request, his brother forwarded him copies of other emails which had nothing to do with the last will.

But PM Lee said his brother "cut out and did not send me the incriminating exchanges in the email chain that followed".

These deleted parts showed Mr Lee Hsien Yang's and his wife's involvement in the making of the last will in December 2013.

PM Lee said that he continued to have grave concerns about the events surrounding the last will.

He also said he was not aware of any facts that suggested his father was informed or advised about all the changes that were made when he signed the last will.

"In fact, there is no evidence that Mr Lee even knew that the demolition clause had been re-inserted into the last will," added PM Lee.

In his statement, he listed a series of questions he had, including whether his father gave specific instructions to re-insert the demolition clause in the last will, and if so to whom.

He also asked about what role Mrs Lee played in the preparation and signing of the last will, and whether she, her fellow lawyers, and her law firm had a conflict of interest.

Said PM Lee: "Without proper and complete answers to these questions, the serious doubts about whether Mr Lee was properly and independently advised on the contents of the last will before he signed it cannot be cleared."