To reinforce the necessity to obtain a legal consultation before completing or re-doing a will, just look at some of the many reasons legal advice is specifically required because of the complex legal issues and options involved:
you are separated from your spouse but not divorced
you are divorced and want to re-marry
you are divorced and paying for the support of your former spouse and children
you are living common-law, will be entering a common-law relationship, or leaving an existing one
you have a same-sex partner
you are in a blended family relationship, with children of each spouse from previous relationships
you have children from a previous relationship and an existing one
you own your own business or are part-owner with other partners
your estate is large and you need assistance with estate planning long before your death to reduce or eliminate taxes on your death (discussed later)
you have a history of emotional or mental problems such that someone could attack the validity of your will on the basis that you did not know what you were doing when you signed the will, or were not capable of understanding the financial matters covered in the will
you want to have objective, unbiased and professional advice rather than making choices in a vacuum or possibly being influenced by others who have a vested interest in the contents of the will
you want to live in the U.S. or elsewhere for extended periods of time (the issue of your technical domicile, or permanent residence at the time of your death has legal and tax implications in terms of your will)
you own or plan to own real estate in the U.S. or elsewhere
you have a will which was signed outside Canada or plan to do so
you want to forgive certain people for debts they owe you, or make special arrangements for the repaying of debts or mortgages to your estate should you die before the debt or mortgage is paid back to you
you want certain events to occur which are complicated and have to be carefully worded, such as having a spouse or friend have a certain income or use of a home until they re-marry or die and at that time the balance of money or house goes to someone else
you want to set up a trust arrangement to cover various possibilities
you want to make special arrangements to care for someone who is incapable of looking after themselves, or has shown themselves unable to apply sound financial or other relevant judgement (a child, an immature adolescent, a gambler, an alcoholic, a prodigal child, a spendthrift, or someone who has emotional, physical or mental disabilities or limitations or who is ill)
you wish to disinherit a spouse, relative, or child for a variety of reasons (For example, you may have lent a lot of money to one child out of several and the money was not repaid and promises were broken and a serious estrangement occurred. The debt substantially reduced your estate. Another more positive reason is that all your children are now independently wealthy and don’t need your money. You may therefore want to give the majority of your estate to charitable causes.)
you wish to appoint a guardian to look after your children in case you and your spouse die together
you have several children and you want to provide the opportunity for one specific child to buy, have an option to buy, or receive in the will the house, business, farm or a specific possession or asset of your estate, and want to set up the appropriate procedures and wording to enable your wishes to occur.
As you can see, when projecting your circumstances in the near future, there could be many different reasons to consult with a legal expert on the topic of wills.